SoreFeet

I'm wondering if anybody has tried using a large 29er tire on an old road bike. I've got the appropriate road rims and am using a 35C tire...Is it possible to squeeze one in with Mafac Racer brakes?

nlerner

What bike do you have in mind? Something that had 27" wheels originally is likely to have the most amount of clearance, but your pickings will be fairly limited.

Neal

kramnnim

I don't see how it would be possible... Someone gave me a 700c cross/touring/hybrid fork advertised as a 29er fork, and I couldn't even get the axle into the dropouts... (this was with a 2.1" 29er tire mounted on a ~19mm wide rim)

Ronsonic 

Really depends on the bike. 35s are probably possible if you're willing to let the air out every time you put them on and your rims are straight as the truth. I doubt you could go bigger than that.

I've run 32s on an early nineties road bike, but that was with true rims and letting the air out to get them past the brake shoes.

Flying Merkel

I'm in the midst of such a conversion. The bike is a Schwinn Mirada that originally came with a 650b rimset. Cut away the brake bridge & the fender thingy in order to get the tires to fit. Using 700c x 38s. The bike originally was a mountain bike, so it has V-brakes. I have access to brazing gear & a sense of humor, so the missing frame pieces will be replaced. With the rear tire pumped up to 80 lbs, it cleared the offending pieces & rode decently. Had to cold set the frame to get the new 8-speed rear hub to fit. Another first for me.

Pumped the rear tire up to the full rating of 100 pounds. 5 minutes later it exploded in my hands as I was fitting it to the frame. Seems the cheap C-list wheelset was cheap for a good reason. The rear is slightly flat. The tires fit loose, so the drama was inevitable. Sounds like a large caliber weapon going off. The boys in the hood hit the deck. Memories of a recent drive-by are fresh.

I get to learn how to build wheels- yet another first. The poor Schwinn was only $25.00. The original steel wheel were seriously warped and replacements are expensive if you can find them. This was my justification.

The short ride I did have was stately, with skyscraper views & ocean liner handling. This is my Fred bike- to be ridden with ordinary shoes to the beach or tavern. Stability will be a plus. Pictures will follow.

redxj

Just a FYI that a 29er tire is not a 700x 38 or anywhere close too it. 29er tires are almost all off road knobby tread tires with at least a 2.0" width (50mm+ width).

Now you can often fit large hybrid/touring tires in some of the older bikes. 700x by 35-40mm width would be possible on some bikes. Like Neal mentioned a stock 27" sport/touring bike of the 70's/80's can often fit 700c x 35s easily. I had knobby 35mm wide cross tires mounted in my Nishiki Seral touring bike (original 27" wheels). I dropped down to a 32mm wide road tire so I could add fenders to it.

riva

Yer, 32 to 42mm wide 700's are commuter/cross sizes. 29'er tires are huge. I don't think 2.0+ would fit even on most of the cross or hybrid bikes out there let alone road bikes.